Edward Snowden documentary chronicles intelligence leak

Citizenfour is a documentary that chronicles one of the biggest intelligence leaks in American history.

It shows former National Security Agency contractor, Edward Snowden, at the very moment he made his sensational revelations detailing extensive internet and phone surveillance by the US government.

It is up for an Oscar, but may split voters given that many Americans view Snowden as a traitor.

Talking Movies' Tom Brook reports.